Han'guk Tongnyŏk Chawŏn Yŏn'guso

• Chawŏn hwaryong yŏnʼgu
• Kuktʻo iyong chijil chosa yŏnʼgu
• Kŭmsok kwangsang chosa yŏnʼgu
• Uranyum kwangyŏk tʻamsa yŏnʼgu